The world's largest island is Greenland, with an area of about
822,700 sq mi / 2,130,800 sq km. Largely covered by an ice-cap several
thousand feet / meters thick, Greenland has a population of only about
40,000, about 1/40th of Manhattan's, though Manhattan is 37,000 times
smaller.

The world's largest river island is Ilha do Bananal, a
7,720 sq mi / 20,000 sq km island formed by two channels of the Araguaia
River in Tocantins State, Brazil.

Ilha de Marajo, a 15,500 sq mi / 40,100 sq km island in
Para, Brazil, is mostly surrounded by channels of the Amazon and Para rivers,
but also extends into the Atlantic. It is the world's largest island formed
by fluvial processes.

Bishop Rock, in the Isles of Scilly off southwest England,
is sometimes called the world's smallest island, but this is an unwarranted
claim based on an arbitrary 19th century bureaucratic classification scheme.
It is impossible to determine an actual world's smallest island.

Under certain conditions, the criteria for an island—a
fairly permanent piece of land surrounded by water and possessing substantial
vegetation—can be met by an islet of less than 100 square feet.

There are several places where islands on islands in turn
have lakes with islands – triple islands.The largest island on an island on an island is a 4 acre / 1.6 ha
island in a lake on an island in a lake in south-central Victoria Island,
Nunavut, Canada, at 69.7928° north, 108.2411° west.

An island in a crater lake on Volcano Island, Lake Taal,
Luzon, in the Philippines, is often said to be the largest island in a lake
on an island in a lake on an island, but the one in Newfoundland is about
twice as large.

The largest island created by human action is the Île
René-Levasseur, a 780 sq mi / 2,020 sq km island in Manicouagan Reservoir,
Quebec. The reservoir was formed by the damming of a river to flood a 210
million-year-old meteor crater, whose central uplift became the island.

The largest raised coral atoll is Lifou (Lifu) in the
Loyalty (Loyauté) Islands of New Caledonia. With an area of 443 sq miles /
1,146 sq km, it is larger than Rennell Island (255 / 660) in the Solomons, as
well as smaller islands such as Aldabra.

Tristan da Cunha, a 38 sq mi / 98 sq km volcanic island in
the South Atlantic with a population of 300, is 1,320 miles / 2,120 km from
the island of St. Helena, the nearest inhabited land, and 1,700 miles / 2,740
km from the nearest continent, Africa.

Easter Island (Rapa Nui / Isla de Pascua) is sometimes
described as the most isolated inhabited island on Earth, but is closer to
inhabited land (Pitcairn I.) than Tristan da Cunha, and closer to a continent
than many islands of the central Pacific.

The most northerly island, and the northernmost point of
land in the world, is a tiny unnamed island at 83o 40'
34.8"N, off the north coast of Greenland. It was not discovered until
1996, and is north of Oodaaq Island, the previous holder of the record.

The southernmost named island is Deverall Island, a small
ice-covered island in the Ross Ice Shelf, Antarctica, at 81o 28'
S, 161o 54' E.

The first islands appeared on Earth about 4.4 billion
years ago, when the oceans formed. However, most islands now in existence are
extremely young, the result of sea level changes and glacial retreat over the
last 12,000 years or so.

The island that has existed longest is Madagascar, which
separated from India perhaps 85 to 90 million years ago, after the two had
split off from Antarctica about 125 million years ago.

A volcanic island erupted from the sea on June 6, 1995, at
Metis Shoal near Tonga's Vava'u Group. By the following month, it was
estimated to be 21 ac / 8.4 ha in area, and 178 feet / 54 meters high. Some
proposed naming it Lomu Island, after a rugby player of Tongan ancestry.

However, it was thought that the island may be merely the latest
incarnation of an island which has appeared near that site several times
before, most recently as Lateiki Island, which existed from 1976 to 1978. The
new island might survive for only a few years before eroding or subsiding
beneath the waves.

Fukoto Kuokanaba, a volcanic islet in the Pacific near the
Japanese island of Iwo Jima, was first reported in January, 1986, and is
about 50 acres / 20 hectares in area.

Kavachi, an undersea volcano in the Solomon Islands,
erupted in spring 2000, but is not known to have formed an island.

Ap Lei Chau, off the southwest side of Hong Kong Island,
is the world's most densely populated island, with 80,000 people living in
0.5 sq mi / 1.3 sq km, for a density of 160,000 per sq mi / 60,000 per sq km.

Male, in the Maldives, is the world's most densely
populated unbridged island, with about 70,000 people living in 0.68 sq mi /
1.77 sq km, for a density of 103,000 per sq mi / 40,000 per sq km. With an
additional 20-30,000 visitors at any one time, Male achieves densities of
130-160,000 per square mile / 50-55,000 per sq km.

Singapore is the most densely populated all-island
country. With 4.0 million people (as of 1999) living in 247.6 sq mi / 641.4
sq km, it achieves densities of 16,160 per sq mi / 6,240 per sq km. However,
most Singaporeans live on the main island of Singapore, which is connected to
the mainland by a solid causeway, and is thus not strictly speaking an island
at all.

Before it reverted to China in 1999, Macao held the
density record. Occupying the tip of the island of Zhongchan Dao and two
small islands, Macao's 502,000 inhabitants live in 6 sq mi / 16 sq km, for a
density of 84,700 per sq mi / 31,400 per sq km. All Macao's islands are connected
by bridges to the mainland.

The non-coastal island country with the highest population
density is Malta, with 377,000 people living on islands with a total area of
124 sq mi / 320 sq km. This translates to a density of 3,050 per sq mi /
1,180 per sq km.

A close second is Bermuda, a British colony in the
Atlantic east of the United States. With about 62,500 inhabitants in 20.6 sq
mi / 53.3 sq km, the island group has a density of 3,040 per sq mi / 1,170
per sq km.

The least densely populated inhabited island is Ellesmere,
in Nunavut, Canada, with 153 people on an island of 75,767 sq miles / 196,236
sq km. Each inhabitant thus has 495 sq miles / 1,283 sq km apiece.

This is 51 million times less than the density of Male, in
the Maldives.

The Maldives is the lowest island country. Its tallest
island, Wilingili, rises only 8 feet / 2.4m above sea level. The Maldives is
among the nations most concerned about potential sea level rise brought on by
global climate change.

The smallest island shared by two countries is not Saint
Martin / Sint Maarten, as commonly asserted, but instead the middle island in
Södra Boksjön, a lake on the Norwegian-Swedish border. It is about 0.2 acres
/ 0.1 hectares. St. Martin is 34 sq miles / 88 sq km.

The smallest sea island shared by two countries is Märket
/ Märketin, a rock islet divided between Sweden and Finland in the Baltic. It
is 8 acres / 3.3 ha, and features a lighthouse.

The only island shared by three countries is Borneo, in
Southeast Asia, which is split between Indonesia, Malaysia, and Brunei.

Cyprus is divided into
Cyprus, Northern Cyprus, and two U.K. Sovereign Base Areas, but Northern
Cyprus is a Turkish-supported de facto state in the north part of the island,
unrecognized by the international community. The British bases are military
outposts.